Threading device.



c. F.'sCHuLTls.

THREADING DEVICE. APPLICATION FILED DEC. 8, |4910.

Patented. Apr. 13, 1915.

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llllnllllll 415%@ ym W azi f/m B7 fanfar- All d l l l c. F. SCHULTIS. THREADINGv DEVICE.

APPLICATION FILED DEC.8. 1910.

d Apr. 13, 1915.

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CHRISTIAN GIRL, 0F

CLEVELAND, OHIO.

THREADING DEVICE.

Specification of Letters Patent.

Patented Apr. 13, 1915.

Application filed December 8, 1910. Serial 1\T o. 596,199.

T0 all whom it muy/concern Be it known that I, CHARLES F. SoHULTIs, a citizen of the United States, residing at Cleveland, in the county of Cuyahoga and State of Ohio, have invented a certain new and useful Improvement in Threading Devices, of which the following is la full, clear, and exact description, reference being had to the accompanying drawings.

rlhis invention relates to screw threading devices, and particularly tovdevices or tools of this class which embody dies for cutting threads and wherein the dies are adapted and constructed to open automatically.

One of the objects of this invention is lto provide an improved construction whereby, when the work has been threaded a certain distance, the dies will be automatically opened, thereby obviating the necessity of reversing the lrotation of the tool or of the work, to withdraw the latter.

A further object provide eflicient means whereby, when the end of the thread is reached on. the work, and it is impossible to advance the work on the tool, further rotation of the work or of the tool will not result in stripping the thread, but will cause the dies to automatically open and release the work.

A still further and general object of the invention is to provide a tool of the character set forth, which is simple and economical of production and eiiicient in operation.

l' accomplish the foregoing objects by the construction illustrated in the drawings hereof, wherein- Figure 1 represents a side elevation, with parts broken away, of a device constructed in accordance with my invention; Fig. 2 a front elevation of said device; Fig.u3 a side elevation of the device taken at about right angles to Fig. 1; Fig. 4. a central longitudinal section through said device; Fig. 5 a view similar to Fig. 4;, showing the jaw 1evers opened by the movement of the abutment; Fig. 6 a similar view showing the jaw levers opened by the forward movement of the levers, and Fig. 7 a sectional view on the line 7-7 of Fig. 5.

The tool illustrated herein is a die stock which is adapted to be mounted either in a machine of the turret type, in which the tool is securely fixed while the work is fed thereof the invention is t0v to, or in a machine in which the tool is rotated and moved endwise while the work is fixed, asl in certain types of screw machines, or in a machine wherein the tool is rotated andlthe work is fed thereto.

Describing the parts by reference char acters, 1 denotes the shankof the tool,` said shank having ahead 2 preferably integral therewith. The shank is provided with a central bore 3, said bore merging with an enlarged recess or chamber t inthe vicinity of the head of the tool and this recess in turn Vmerging with a larger recess or cha1nber 5 formed within the head. This last recess or chamber may be square in section.

The head proper is provided with a central chamber 6, extending substantially the full length thereof, and with a pair of opposed recesses extending from the outer periphery thereof into and communicating with the chamber, said recesses forming guide-ways for a pair of levers which carry the dies or chasers. These recesses are indicated 4at 7 and the levers referred to are indicated at 8 and are constructed and secured in place as follows: Each lever has in the front endthereof a recess extending outwardly from the inner face thereof, said recess being` enlarged from front to rear by flaring the lateral sides thereof (as will appear from Fig. l) to give it a dove-tailed shape and adapt it to receive the correspondingly shaped die or chaser 9. To lock the dies or chasers in place, screws 10 are provided, each extending laterally through a jaw, through one of the Haring sides of the recess and bearing against a die and, in order to adjust the dies, the screws 11 are provided, each extending through a jaw and bearing at its inner end against the outer portion of the die.

Each lever 8 is provided at its rear end with an' inwardly projecting portion or flange 12 and the inner face of each lever is recessed, as shown at 13, the purpose of so reducing the thickness point being not merely to reduce the weight of the same, but to afford a convenient means for compensatingfor the wear produced between the inner ends of the flanges 12 and a coperating member, to be described hereinafter. Each of the levers is provided with a slit 14 extending forwardly from the rear end thereof and providing a of the levers at this if L30 Y Y Y i seats are conveniently Vformed by providing i relatively thinand'flexible body 15 between said slit and the recessed portion 13, said vbody carrying the projection or flange 12,.l kEach lever is providedv withfa'v threaded bore extending from theouter surface inwardly to the slit 14 and in this bore thereV is mounti edV a screw-threaded stud 16, the studbeing provided withnotches 17 for the reception ofa Vscrew driver or similarV adjusting means.Y Y

Each'lever 48 Vis provided with a bore 18 extendingrrearwardly fromV the front face thereofjand substantially'parallel with the axis of the' tool, the bore being loeatedr'p'referably'at some point between the recess for thev die '9 andthe outerperiphery ofthe Y. lever, Each lever-is provided with. an elon- 'gte and f intersecting the bore 18. the rear endxof each" bore `1 8 there is inserted av heli- *cal springv 2O'l and in front of this spring Y. therev is inserted a short rod 21, said rod being vprovided''with a transverse bore.4 The levers 8 are pivotally connected tothe head l2 vbymeanslof a pin 22 extending through y' the transverse Vbore providedv in each .rod

fand through the slot 19in the lever, the pin having its outer endY portions anchored in seats p'rovi'dedftherefor inthe head and on opposite sides of each recess 7. These r`angularrecesses 23 inopposite sides ofthe 'head2 and' 'by ,boringv through the reduced portions of-the fhead thusy provided, at rightfangles `to the bore 18, VWhen the parts are in oA erating position, the pin exy tendsthrough the front end ofits 'slot 19 as shownV in Fig. 4.'

" Tl'ie head 2 is{p rov1ded acylindrical .re'cess inits outer periphery adapted to receive `aV metallic ringf`25, the outer surfacevr Y oftheV ring beingpreferably flush with the Y' l rearlsur'face ofthe hea-dV and the rear end of t'l'ie vringY abutting `against' .a shoulder 26 formed on the head. For agpurpose to be Y explained hereinafter, .each stud 136 Y` is L v drilled outto .provide a recess 2 7' intowhich theme is inserted aV helical vspring 28, the

inner endv'of whichbears againstthe .bot-- tom of the cup there formed and the outer end Vag'rainst Vthe ring orv shellV 25. 1

Munaed' within the bore s is a'rod 29,

" :which rod .projects into the. central chammounted'an abutment 30, saidabutmentbe- 'jflthereof. The abutment is `secured -to .the

rod'by means V.ofla set screw 32 in the head shell 25 and through asuitable borel provided in-the abutment.l

. Y 'n the chamber 4 there is mounted al helicalfl spring 34,- one end ofv which bears against .the'rear'of said chamber and at` the ,I oppositepend against the rearend of the .slotfV 19 extending thronglrthe same abutment;A This spring will normally hold the abutment and the rod 29 in the position shown in Fig. 4, with the projections 12 bearing against the opposed .faces of the abutment 30 and just at the rear of the notches 31. A helical spring is mounted in the bore 3 and bears at one end against therear end of the rod 29 and at its other end against an adjusting screw 36. The spring 35 forms ayielding resistance to the rearward adjustment of the rod 29 and will also assist the spring 311 in holding the rod y andthe abutment intonormal or forward position;

The operation ofthe device is as follows:

TheV rod 29 will be set; within the chamber 6 to thelength of the thread to be cut upon the work. Y Vif-henl the work engages the front end of the rod 29, whether the work be fed toward the tool or vice versa, the rod 29 will be thrust rearwardly against the action of the vsprings 341 and 35, carrying with it the abutment 30. lAs soon as the notches 31 are Amoved rearwardly a sufficient distance, the springs 28 will force the flanges 12 into said'. notches, rocking, the levers 8 and disengagingfthe dies 9 from the work, asgshown'in Fig. 5. The work can then be withdrawn from the tool without the necessity of rreversing the rotation of the tool or the work. ,When so withdrawn, kthe levers vmay be rocked on their pivots' by `merely grasping vthe projecting front ends of the same andpressing them toward each other. This will pressftherear .ends of the levers outwardly and-allow the-springs 34 and 35 to restore the n rod 39jand abutment 30 to their vnormal position. The movement of Vthe rod and abutment is permitted Yby the elongated slot 33, through which the screw 32pprojects; Suppose. the thread has been cut y as faras possible on the work, further A.advance being prevented by. the stop usually provided, further rotation of the work or the tool, as the case may be, will produce a forward pull upon the levers S, through the engagement of the 'die threads with the threads on the work. This pull will move the levers 8 forwardly, through the slots 19 on the pins. 22, bringing the projections 12 into register with the notches 31, whereupon the springs- 28 will force the inner ends of lthe levers inwardly and automatically separate the-front or outer end of the levers,.asshown in Fig. 6. "The parts may be restored ,tol normal position by pressing the'pfront ends of the levers toward each other,`thereby releasing the projections 12 lfrom .the notches 31. Thev springs 20 will movethe levers 8 rearwardly, through their y engagement with-the rear ends of the rods 21, .whichfare rigidly pinned to the head 2. These springs normally hold rthe levers in their rearward position, with the pins 22 bearing against the front ends of the slots 19. As the abutting portions of the projections l2 and of the abutment 30 are liable to wear and thus produce a corresponding variation in the distance between the dies 9, this wear can be readily compensated for by threading the screws or plugs 16 inwardly into their respective bores and thereby forcing inwardlythe projections l2, this result being made possible and convenient of accomplishment by the slits 14 and the reductionin thickness of the metal between said slits and the inner surfaces of the levers adjacent thereto.

Having thus described my invention, what claim is l. In a device of the character set forth, the combination of a shank, a slotted head carried by ber therein, die-carrying levers pivotally mounted in the slots insaid head, springs tending to force the rear ends of said levers inwardly, a rod slidably mounted in said shank and projecting into said chamber, an abutment adjustably mounted on said rod, and means yieldingly projecting said rod and abutment forwardly in to said chamber,

the abutment and the portions of said levers which are at the rear of their pivotal conneotion having coperating abrupt portions adapted to be moved past each other when the abutment is moved rearwardly, so as to permit the abruptinward movement of the rear ends of said levers.

2. In a device of the character set forth,

the combination of die-carrying levers, means pivotally supporting said levers intermediate of their ends, springs forcing the rear ends of said levers inwardly, an abutment projecting between said levers and adjacent to the rear ends thereof, and a spring resisting the rearward movement of said abutment, there being a guideway for the abutment and said abutment being provided with abrupt notches for the rear ends of said levers and with supporting surfaces for such ends at the rear of said notches, andV said levers having inwardly projecting end portions adapted to engage said surfaces and to enter said notches.

3. ln a device of the character set forth, the combination of die-carrying levers. means pivotally supporting said levers intermediate of their ends, springs forcing the rear ends of said levers inwardly, an abutment projecting between said levers adjacent to the rear ends thereof and slidably mounted within a guidesway provided therefor, a spring resisting the rearward movement of said abutment, said abutment being provided *ith notches for the rear end portions of said levers and with supporting surfaces for such ends at the rear of said notches, and said levers having inwardly projecting portions adapted to engage said surfaces and enter said notches, and means said shank and having a cham-L whereby the inwardly projecting end portions of the levers may be adjusted toward the abutment, independently of the bodies of the levers, to compensate for wear.

a. In a device of the character specified, the combination, with a supporting member, of die-carrying levers pivoted transversely thereof, means for permitting a limited longitudinal movement of said levers relative to said supjiiorting members, dies carried by the front portions of said levers and means carried by Vsaid supporting member and movable relatively thereto for governing the position of said levers, said means and levers being so arranged that upon relative movement either caused by contact of the means with the end of the work or the forward movement of the dies along the thread of the work, the levers will swing upon their pivots and cause the dies to release the work.

5. Ink a device of the character specified, the combination of a pair of die-carrying members, supports therefor, a pivotal connection between each member and its support allowing said member to be-moved forwardly with respect to said support, and means operating to automaticallyV separate the die-carrying portions of said members when the latter are moved forwardly with respect to their supports.

(i. ln a device of the character specified, the combination of diecarrying members, supports therefor, means pivotally connectw ing said members and said supports, such pivotal connection allowing each member to moviJ forwardly with respect to its support, means tending to move inwardly the portions of said members which are at the rear of their pivotal supports, and means normally preventing such inward movement.

7. In a device of the character specified, the combination of die-carrying members, supports therefor, each of said members having an elongated slot, a pin mounted in the support and extending through the slot and pivctally connecting each member to its support, a spring pressing each member rearwardly with respect to its support, means pressing inwardly the portionsof said members which are located at the rear of their pivotal supports, and means normally preventing such inward movement.

S. ln a device of the character specified, the combination of die-carrying members, each of said members having a longitudinal bore and provided with an elongated transverse slot extending therethrough and intersecting said bore, a spring in each bore at the rear of said slot, a movable abutment in each bore having its rear end operatively engaged by the spring therein, a support for each Vof said members, a pin mounted in each support and extending through said slot and said abutment, means forcing inwardly the portion of each member which is at the rear ofV ritspivotal connection YWith bore'and provided with an elongated trans- .verse slot .Y extending vtherethrough'` and intersect-ing said bore, a spring in eachV bore .at the. rear of said slot, a 'movable abutment in each A,bore having its rear lend Voperatively engaged by the spring therein, a support,vr for eachl of said 'members a pin' mountedv in each support Y andV extending through said slot and said abutment, means forcing inwardly the portion of each member which is at the'rear of vitsA pivotal connection with 1ts support, an

.Y CHARLES F. SCHULTIS.

Witnesses p 1 J.-B. HULL,

VBRENNAN B. VVEsT.

VCopies of this patent may bewobtaned fiorve cents each, by addressing `the Commissioner of Patents-r Y Washington, D. C. 

